Generally, Ethernet interfaces provided by a switch include layer-2 Ethernet ports. The layer-2 Ethernet port is one of the physical interfaces on the switch, works in a data link layer, processes layer-2 protocols, and implements layer-2 transmission. In addition, layer-3 Ethernet interfaces are also one of the interfaces on the switch, works in a network layer, configures Internet Protocol (IP) address, processes layer-3 protocols, and provides route functions.
When a switch processes packets received from the Ethernet interfaces at different layers, some Ethernet interfaces may work in a bridging mode or in a routing mode, and these kinds of Ethernet interfaces are called layer-2/layer-3 switchable Ethernet interfaces. When the Ethernet interface is configured in the bridging mode, packets are transmitted through hardware of the switch, and the Ethernet interface cannot configure IP addresses. When the Ethernet interface is configured in the routing mode, packets are transmitted according to layer-3 IP route.